1. Field of the Invention
The present invention relates generally to ocular surgery, and more specifically to controlling multiple pumps in a medical system, such as a phacoemulsification system, configured for concurrent operation from a footpedal during ophthalmic surgical procedures.
2. Description of the Related Art
Phacoemulsification surgery has been successfully employed in the treatment of certain ocular issues, such as removal of a cataract-damaged lens and implantation of an intraocular lens. Phacoemulsification surgery typically involves removal of the cataract-damaged lens utilizing a small incision at the edge of the cornea. Through the small incision, the surgeon then creates an opening in the capsule, i.e. membrane that encapsulates the lens.
The surgeon can insert an ultrasonic probe, incorporated within a phacoemulsification handpiece, through the opening in the cornea and capsule, thus accessing the damaged lens. The handpiece's ultrasonically actuated tip emulsifies the damaged lens such that the lens can be evacuated by the handpiece. After the damaged natural lens is completely removed, the handpiece tip is withdrawn from the eye. The surgeon may now implant an intraocular lens into the space made available in the capsule.
Today's fluidic-based systems typically use various pumps, and frequently employ two general types of pumps for aspirating lens material. A flow based fluidic system, operating a peristaltic/scroll pump, generates vacuum when the aspirating tip becomes occluded/blocked. A vacuum based fluidic system, operating a venturi/rotary vane pump generates vacuum though air pressure using either an internal or external air source and a reservoir. Multiple pump systems are being employed in current phacoemulsification devices, and other types or styles of pumps can be employed beyond the aforementioned peristaltic and venturi pumps.
While performing phacoemulsification surgical techniques, such as lens removal, a surgeon may wish to employ either a flow based pump or vacuum based pump to irrigate and aspirate the eye. Current designs limit the surgeon/operator to selecting between flow or vacuum based functionality, unable to provide for operating both flow and vacuum based systems concurrently or sequentially using a single software application and controller, such as a footpedal.
Previously available fluidic-based designs typically provided for operation of a single pump within the controlling software application. If the surgeon determines during the procedure a need to switch from, for example, flow to vacuum based functionality, the surgeon has been required to change or switch sub-mode operation within the software application to affect the desired aspiration source type. Switching sub-mode operation in this manner took time to switch between pumps and tends to be unwieldy during operations.
In a situation where the surgeon/operator manually switches pumps, the transition from, for example, flow based operation to vacuum based operation over a period of time may introduce undesirable ocular chamber instability during the transition. Instability results from the transition time switching between pumps, as such a lag may result in a loss of pressure in the eye and/or fluid flowing out of the eye, both highly undesirable occurrences.
Based on the foregoing, it would be beneficial to offer a design for seamlessly switching between multiple aspiration pumps when using an ultrasonic handpiece in an ocular surgical procedure that overcomes drawbacks present in previously known designs.